Research news, Aug. 26th, 2014
Novel Reactivities of 2,2-Dichloroimidazolidine-4,5-diones: Synthesis of Copper(I) Diamidocarbene Complex, 2-Thioxo/Selenoxoimidazolidine-4,5-dione and 2,2-Difluoroimidazolidine-4,5-dione
Fei Zhao, Yang Wang, Ling Xu, Wen-Xiong Zhang,* and Zhenfeng Xi.
Tetrahedron Lett. 2014, 55, 4579-4600.
A new method for the in situ generation of five-membered diamidocarbenes (DACs 2) from 2,2-dichloroimidazolidine-4,5-diones is established by Cl/I exchange and elimination of iodine. The trapping of 2 with CuI, S and Se provides a good route for the preparation of a dimeric (2a)CuI complex and 2-thioxo/selenoxoimidazolidine-4,5-diones, respectively. In contrast, Cl/F exchange is explored to yield exclusively 2,2-difluoroimidazolidine-4,5-diones.